Motor-barrel watch movement

ABSTRACT

A motor-barrel watch movement in which the barrel arbor is cylindrical with longitudinal grooves one of which acts as the spring anchor. There are four bearing regions for supporting the pivoting of the arbor in the frame and the pivoting of the barrel on the arbor.

[ 1 Nov. 12, 1974 United States Patent [1 1 Giger MOTOR-BARREL WATCHMOVEMENT Inventor: Urs Giger, Solothurn, Switzerland [73] ASSigneeI EtaA.G. EbalICheS-Fabri Primary Examiner-Ge0rge H. Miller. Jr.

Grenchcn, Switzerland Attorney, Agent, or Firm-Stevens, Davis, Miller &22 Filed: Nov. 16, 1973 Moshe [21] I Appl. No.: 416,430

Foreign Application Priority Data Dec. 18, 1972Switzerland.......................

ABSTRACT A motor-barrel watch movement in which the barrel [52] US.58/87 arbor is Cylindrical with longitudinal grooves one 0f 51 Int. Cl.G04b 1/18 w i h acts as the spring anchor There are four bear- [58]Field of Search...................;....... 58/86, 87, 139 g regions forsupporting the pivoting Of the arbor in a the frame and the pivoting ofthe barrel on the arbor.

References Cited UNITED STATES PATENTS 9 Claims, 2 Drawing Figures1,110,061 9/1914 Kienzie 58/86 Z: fgwk SUMMARY OF THE INVENTIONEssentially the object of the present invention is to achieve areduction in manufacturing costs of motorbarrel watch-movements bysimplifying the barrel arbor and the motor assembly.

In most watch movements, the barrel arbor willbe a profile-turned'partwith six to eight shoulders of different diameters along its length.Furthermore, the central part, which is of maximum diameter, isprovided-with several millings forming a hookto which is fastened theinside end of a spring-motor also equipped with a hook formed by bendingthe spring ata right angle. Of those shoulders of different diameters,four are used for pivoting and cons-equentlymust be machine finished. Itwill be clear that under such conditions, the manufacture of thesebarrel arbors consists of a sequence of costly operations; 1

Cylindrically shaped barrel arbors already. are known, which aredetachably mounted in the movement frame. However, as regards theseknowndevices, an additionalpiece-acting as core, that is, as thecentralcomponent of the arbor, and ensuring that the springmotor is hooked,will be placed inside the drum. This additional piece is provided with acylindrical passage in the direction of its axis, and'the cylindricalarbor will be placed inside said passage. Also, the core must bemachined together with its hook. Further, the detachable arbor isprovided with a pivoting shoulder which must be machined on the lathe.While such a known device facilitates barrel disassembly,it-does-nothing to simplify the manufacture of the arbor and will .not

lower its manufacturing cost.

Cover-less barrels provided with an elongated hub known. However, asregards these known devices, the core again is a separate piece whichmust be mounted on the arbor where it will form a separate collarsurrounding the hub of the drum, whereby arbor machining is considerablyhampered.

Lastly, barrel arbors are known, wherein the core hook is replaced by agroove running parallel to the barrel arbor and fashioned into itscentral shoulder. In these devices again, many manufacturing operationsare required to achieve the arbor.

In order to reduce the number of operations involved in the manufactureof a barrel arbor and to facilitate assembly of the motor-sets forwatches, the object of the present invention is a motor-barrelwatchmovement characterized in that the barrel arbor is made of onepiece provided with anchoring means for the spring-motor and with acircular surface the pivoting of the arbor in the movement frame andpivoting of the barrel about the arbor is oriented by four annularcomponents bearing-on said cylindrical surface of said arbor. Theseannular components extend to the level of the apertures made on one handin two components of the frame and on the other hand in the drum and inthe barrel cover.

The attached drawing illustrates two embodiments of the watch-movementof the invention.

FIG. 1 is a fragmentary view in cross-section of one of thoseembodiments taken in a plane containing the barrelaxis; and

and mounted on ;a long cylindrical shoulder are also ing'machining andwhic arbor 1.

2 FIG. 2 is a fragmentary view in cross-section of the other of thoseembodiments also taken ina plane containing the barrel axis.

As will be observed from the present description, the

two embodiments shown in the drawing maybe executed as differentvariations of the barrel arbor. The first embodiment relates to awatch-movement in which the ratchet-wheel 2 is mounted on the arbor ofbarrel 1 and lies between the drum of barrel 3 and the bridge of barrel4. A cover 14 is fastened to the drum of barrel 3, these two componentsbeing bored by central apertures 5 and 6 of the same diameter. Further,aperture 7, which'is fashioned in bridge 4 in order to ensure rotationof the upper end of arbor'l, and aperture 8, which is fashioned in thebottom plate 9 to ensure the rotation of the lowerend of arbor l, are ofthe same diameter as apertures 5 and '6, however, aperture 8 beingpartly closed towards the outer side of the bottom plate by an annularflange 10 which was made durprovides an axial stop for Arbor l is madeof a simple piece and is'mainly characterized'by cylindrical lateralsurface of constant dithe frame in apertures 7 and 8 and rotation of thebarrel about the arbor, by means of apertures 5 and 6. The spring-motor17, therefore, will be provided with a hook at its lower end forentering one of grooves 16.

Arbor 1 may be manufactured in such manner that the cost will beparticularly low. Starting with calibrated cylindrical bars drawn withfour grooves 16,. it will suffice to section these bars on an automaticlathe and to machinethe bevel 11 in order to obtain the arbor blanks.The latter may be tumble-polished, which provides a particularly simpleand effective method for that purpose. Grooves 16 also may be milled,but it is more efficient to draw them. It will beto advantage to foreseeseveral grooves for easier assembly. Once the arbor has been made, theratchet-wheel 2 will be forcefitt'ed on its outer wall, the centralaperture of said ratchet-wheel being provided with two or as many asfour catches 18 adapted to the dimensions of grooves 16. This assemblywill rigidly connect wheel 2 with arbor 1.

It is apparent that ratchet-wheel 2 will engage the movementscrown-wheel which is located inside bridge 4. 5

As regards assembly, spring 17 will be so wound that its last coil willbe of a lesser diameter than that of arbor 1. This spring being housedin barrel 3, 14, the

the .tumble-polishing stage, so that the presenceof must preciselyobserve the tolerances of dimension a v between the lower end of arbor 1and the location of the upper side of ratchet-wheel 2. When inoperation, the positioning of the arbor with respect to height isdetermined on one hand by the flange supporting the lower end of arbor1, and on the other bythe boss 19 in bridge 4 near aperture 7, said bossstopping the upper side of wheel 2. Dimension'd corresponds to the axialplay of the arbor, which may be adjusted by forcefitting wheel 2 to thedesired height a. Dimension 0 between barrel cover and the inside of thebottom plate must be l'argerthanzero. Such an arrangement provides aparticularly simple manufacture of the barrel arbor I The embodiment ofFIG. 2' shows an arbor the same as arbor 1, butofsomewhat differentlocation with respect to the frame components'ln this latter embodiment,theratchet-wheel '20isfastened. as above to the upper end 'of arbor l.Thelatte'rs circular surface traverses aperture 21 inbarrel bridge 22from top to bottom, then passes through aperture 23, of barrel 24, thenaperture 25 of cover of barrel 26, and then aperture 27 of bottom plate28. Spring motor 17 is fastened by its lower endto arbor l in the samemanner as'in FIG. 1.

In orderto ensure that arbor 1 and wheel be kept in a proper axialposition, the crown-wheel 29 is provided with teeth of which the edges290 are slightly sloped with respect to the plane of the wheel. Theteeth of wheel' 20 are similarly inclined. Crown-wheel 29 is maintainedin the axial position by a screw, as in conventional watch movements, sothat the edges 29a lock wheel 20 and arbor l in the axial sense in suchmanner that there will be no play between wheel 20 and geartrain' bridge22. A support plate provided with pins 30 passing through aperturesfashioned in bottom plate 28 and supporting the barrel in the properheight and resting against its cover is used for assembly. This supportmay comprise several pins 30.

This embodiment may be varied by providing the barrel arbor with amachined square at its upper end and with a threaded bore at the axis.In such case, the ratchet-wheel also would be provided with a squareaperture, as in conventional circumstances, and would be fastened to thearbors square by a screw of which the heads diameter would beapproximately the same as the squares diagonal. Such an arrangement alsowould allow to finish the rotational surfaces by tumble-polishing, whichis more effective than rolling.

Another advantage will be obtained from this second embodiment and thevariation that have just been described: the barrel arbor and theratchet-wheel may be easily removed from the frame, as if of one piece.The far hook of spring 17 will be removed the moment the arbor has beenpulled axially over a sufficient length. One may then withdraw themotor-barrel from the movement, provided the components fastened betweenthe barrel bridge and the bottom plate are arranged to leave freepassage to the barrel between the barrel and the periphery of themovement. In lieu of being projusted to the diameter of piece 1 andforce-fitted to vided with catches at its central aperture,ratchet-wheel.

20 might also be provided with a circular aperture adbarrel.

same.

The embodiments and the variation thereof just described provide thefollowing advantages:

One may manufacture arbors l I from, bars with grooves formed thereinduring drawing thanks to a drawing die of suitable shape.

over its entire length, arbor 1 meetsve-ry stringent requirements. Itwas observed that'the initial bars could be trued by means of grindersworking on a rollermounted bar (CENTERLESS process), which factconsiderably simplifies the manufacture and allows achieving highaccuracy. 1

Machining on automatic lathes for bars is extremely simple.

The feasibility of tumble-polishing large quantities of arbors alsoconstitutes simplification in manufacture.

Lastly, as previously. mentioned, the described arrangement facilitatesassembly and'disassembly of the In the case of a self-windingwatch-movement, the pinion(s) meshing with-the ratchet-wheel 6 may bepinions of the self-winding mechanism. They may also be provided withslanting toothing.

As explained above, the use of cylindrical bars extruded through acontoured die for four longitudinal grooves allows particularlyefficient manufacture of barrel-arbors. However, hooking thespring-motor in a longitudinal groove of the arbor is not the soleeconomical solution to the problem in question. Fastening the spring tothe arbor also may be achieved by fashioning an aperture or a cut-out inthe end of the spring and winding latter around itself on the arbor. Thespring then is connected to the arbor byclamping. In this case,

arbor manufacture is particularly advantageous with respect to cost,since one needs only a cylindrical bar which will be sectioned.

. What is claimed is:

1. A motor-barrel watch movement characterized in that the barrel arboris made ofone piece with a circular, cylindricalsurface, and in whichrotation of the arbor in the frame of the movement and the rotation ofthe barrel about the arbor are ensured by four annular bearingssurrounding said cylindrical surface and which lie in the space betweenan aperture fashioned on one hand in two of the frame components and onthe other, in the drum and the barrel cover, said arbor including ananchoring means for the spring motor characterized as a recess formed inthe cylindrical surface of said arbor.

2. A movement as defined in claim 1, in which the barrel arbor is squareat one end, and further comprising a ratchet-wheel-having a squarecentral aperture fastened to said square end of said arbor.

3. A motor barrel watch movement having a barrel arbor and spring motorcharacterized in that the barrel arbor is made of one piece with acircular cylindrical surface and in which rotation of the arbor in theframe of the movement and the rotation of the barrel about the arbor areensured by four annular bearings surrounding said cylindrical surfaceand which lie in the space between an aperture fashioned on one hand intwo of the frame components and on the other in the drum and thebarrelcover wherein said cylindrical surface of said arbor is providedwith at least one longitudinal groove anchoring the inner end of thespring moin that said barrel arbor is tor, and thus constituting theanchoring means therefor.

4. A movement as defined in claim 3, characterized provided with fourlongitudinal grooves at 90 from one another.

5. A movement as defined in claim 3, further comprising a ratchet-wheelprovided with a central profiled aperture with at least one catchcapable of entering said groove, said ratchet-wheel being force-fittedon said arbor with said catch in said groove.

6. A motor barrel watch movement having a barrel arbor and spring motorcharacterized in that the barrel arbor is made of one piece with acircular cylindrical surface and in which rotation of the arbor in theframe of the movement and the rotation of the barrel about the arbor areensured by four annular bearings surrounding said cylindrical surfaceand which lie in the space between an aperture fashioned on one hand intwo of the frame components and on the other in the drum and the" barrelcover wherein the arbor mounting aperture of one of the frame componentsis provided with an innershoulder in the vicinity of its outer sur face,this shoulder acting as an axial step for the barrel arbor.

7 A movement as defined in claim 6, characterized in that saidcylindrical surface of said arbor is provided with at least onelongitudinal groove, and further comprising a ratchet-wheel surroundingsaid arbor and having a catch in said groove, said ratchet-wheel beingadjusted in height on the arbor in such manner that it will lie betweenthe barrel and the frame component ensuring rotation of the arbors otherend, the height adjustment of the ratchet-wheel being such that thiswheel together with the inner surface of said frame component limits theaxial play of the arbor.

8. A motor barrel watch movement having a barrel arbor and spring motorcharacterized in that the barrel arbor is made of one piece with acircular cylindrical surface and in which rotation of the arbor in theframe of the movement and the rotation of the barrel about the arbor areensured by four annular bearings surrounding said cylindrical surfaceand which lie in the space between an aperture fashioned on one hand intwo of the frame components and on the other in the drum and the barrelcover wherein the ratchet wheel is fastened to one end of the arbor andextends outside the frame and in that the axial positioning of the arboris ensured on one hand by a stop rigidly connected to the frame andoperating in concert with the ratchetwheel and on the other by anoblique toothing of a wheel-and-pinion mounted on the frame and meshingwith the ratchet wheel.

9. A movement as defined in claim 8, characterized in that saidwheel-and-pinion is the crown-wheel.

1. A motor-barrel watch movement characterized in that the barrel arboris made of one piece with a circular, cylindrical surface, and in whichrotation of the arbor in the frame of the movement and the rotation ofthe barrel about the arbor are ensured by four annular bearingssurrounding said cylindrical surface and which lie in the space betweenan aperture fashioned on one hand in two of the frame components and onthe other, in the drum and the barrel cover, said arbor including ananchoring means for the spring motor characterized as a recess formed inthe cylindrical surface of said arbor.
 2. A movement as defined in claim1, in which the barrel arbor is square at one end, and furthercomprising a ratchet-wheel having a square central aperture fastened tosaid square end of said arbor.
 3. A motor barrel watch movement having abarrel arbor and spring motor characterized in that the barrel arbor ismade of one piece with a circular cylindrical surface and in whichrotation of the arbor in the frame of the movement and the rotation ofthe barrel about the arbor are ensured by four annular bearingssurrounding said cylindrical surface and which lie in the space betweenan aperture fashioned on one hand in two of the frame components and onthe other in the drum and the barrel cover wherein said cylindricalsurface of said arbor is provided with at least one longitudinal grooveanchoring the inner end of the spring motor, and thus constituting theanchoring means therefor.
 4. A movement as defined in claim 3,characterized in that said barrel arbor is provided with fourlongitudinal grooves at 90* from one another.
 5. A movement as definedin claim 3, further comprising a ratchet-wheel provided with a centralprofiled aperture with at least one catch capable of entering saidgroove, said ratchet-wheel being force-fitted on said arbor with saidcatch in said groove.
 6. A motor barrel watch movement having a barrelarbor and spring motor characterized in that the barrel arbor is made ofone piece with a circular cylindrical surface and in which rotation ofthe arbor in the frame of the movement and the rotation of the barrelabout the arbor are ensured by four annular bearings surrounding saidcylindrical surface and which lie in the space between an aperturefashioned on one hand in two of the frame components and on the other inthe drum and the barrel cover wherein the arbor mounting aperture of oneof the frame components is provided with an inner shoulder in thevicinity of its outer surface, this shoulder acting as an axial step forthe barrel arbor.
 7. A movement as defined in claim 6, characterized inthat said cylindrical surface of said arbor is provided with at leastone longitudinal groove, and further comprising a ratchet-wheelsurrounding said arbor and having a catch in said groove, saidratchet-wheel being adjusted in height on the arbor in such manner thatit will lie between the barrel and the frame component ensuring rotationof the arbor''s other end, the height adjustment of the ratchet-wheelbeing such that this wheel together with the inner surface of said framecomponent limits the axial play of the arbor.
 8. A motor barrel watchmovement having a barrel arbor and spring motor characterized in thatthe barrel arbor is made of one piece with a circular cylindricalsurface and in which rotation of the arbor in the frame of the movementand the rotation of the barrel about the arbor are ensured by fourannular bearings surrounding said cylindrical surface and which lie inthe space between an aperture fashioned on one hand in two of the framecomponents and on the other in the drum and the barrel cover wherein theratchet wheel is fastened to one end of the arbor and extends outsidethe frame and in that the axial positioning of the arbor is ensured onone hand by a stop rigidly connected to the frame and operating inconcert with the ratchet-wheel and on the other by an oblique toothingof a wheel-and-pinion mounted on the frame and meshing with the ratchetwheel.
 9. A movement as defined in claim 8, characterized in that saidwheel-and-pinion is the crown-wheel.